The global contraceptives market was valued at $16.0 billion in 2011 and is expected to grow at a CAGR of 5.9% from 2013 to 2018, to reach an estimated value of $23.3 billion in 2018. The contraceptive market consists of short-term methods such as condoms and oral contraception, long-term methods including implants and IUDs, and permanent methods such as tubal ligations and vasectomies. Eppin Pharma's product has a unique set of characteristics, namely ease-of use, high efficacy, reversibility and no side-effects, that differentiates it favorably from all the other male contraceptive competitors. An important high impact driver of this market is the prevalence of unintended pregnancies. In the US, there are 3.1 million unintended pregnancies annually through inconsistent or non-use of contraception. Eppin Pharma will be competing in the short-term contraception market. The goal of EPPIN PHARMA INC is to develop a non- hormonal male contraceptive drug that targets the protein EPPIN, which is present on the human sperm surface. Unlike hormonal contraception which inhibits spermatogenesis our therapeutic agent, EP055, is present in epididymal fluid and binds to EPPIN on the surface of sperm. The target EPPIN is only present in the male; in testis, epididymis, and on sperm, thereby reducing non-specific binding concerns. The Specific Aims of this STTR Phase 2 proposal are designed to build on STTR phase 1 data and formulate our lead compound, EP055, as an oral male contraceptive that targets EPPIN. Our goal in this STTR phase II application is to collect sufficient pharmacology data to conduct a pre-IND meeting with the FDA. Specific aim 1 will scale up production of purified EP055 to support additional preclinical studies and optimize AlphaScreen assays for formulation products. Specific aim 2 will complete formulation studies with EP055 and create a test batch of tablets for preclinical pharmacology studies. Specific aim 3 will conduct a monkey contraception/fertility study for proof of principle. Specific aim 4 will conduct oral pharmacokinetics studies in rats and monkeys, using oral gavage in rats, oral dosing of tablets in monkeys and conduct dose-range studies for PK/PD assessment.